Canvas covers all

[chirpyform]

Hi,

I've got a serious canvas problem. When I change the size of my window or use a pupup menu the canvas covers everything else. is there anyway of sending the canvas to the background or sending the other components to the foreground ?

Thanks for any help

Chris

 

[Diancecht]

Make the canvas not visible.

Cheers,
Dian

 

[prosper]

Invisible is an idea.
canvas is heavyweight component. There may be some solution in the link.

http://java.sun.com/products/jfc/tsc/articles/mixing/index.html

 

[prosper]

Please look at setDefaultLightWeightPopupEnabled() in my link

 

[prosper]

// copy from web
import java.awt.*;
import javax.swing.ImageIcon;
import javax.swing.JComponent;

class JCanvas extends JComponent
{

JCanvas()
{
}

public void paintComponent(Graphics g)
{
super.paintComponent(g);
g.setColor(Color.white);
}

public Dimension getPreferredSize()
{
return new Dimension(400, 400);
}

public Dimension getMinimumSize()
{
return getPreferredSize();
}

}

 

[chirpyform]

thanks for the replies but in the end i chose to use a JPanel instead of the Canvas class.
However I did lose the focuslistener options and now i must use a popup menu to keep the same level of functionality.

Thanks again

Chris

 

[prosper]

// please extends JComponent
// JMenu part is copied from 
[URL unfurl="true"]http://www.cs.cf.ac.uk/Dave/HCI/HCI_Handout_CALLER/node79.html[/URL]
package org;
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;

public class MyJPTest extends JFrame implements	ActionListener{
	private final int	ITEM_PLAIN	=	0;	// Item types
	private final int	ITEM_CHECK	=	1;
	private final int	ITEM_RADIO	=	2;

	private	JPanel		topPanel;
	private	JMenuBar	menuBar;
	private	JMenu		menuFile;
	private	JMenu		menuEdit;
	private	JMenu		menuProperty;
	private	JMenuItem	menuPropertySystem;
	private	JMenuItem	menuPropertyEditor;
	private	JMenuItem	menuPropertyDisplay;
	private	JMenuItem	menuFileNew;
	private	JMenuItem	menuFileOpen;
	private	JMenuItem	menuFileSave;
	private	JMenuItem	menuFileSaveAs;
	private	JMenuItem	menuFileExit;
	private	JMenuItem	menuEditCopy;
	private	JMenuItem	menuEditCut;
	private	JMenuItem	menuEditPaste;

    public MyJPTest(){
    	getContentPane().setLayout(new GridLayout(1,1));
    	MyJPanel jPanel = new MyJPanel();
    	getContentPane().add(jPanel);
		menuBar = new JMenuBar();

		// Set this instance as the application's menu bar
		setJMenuBar( menuBar );
		
		// Build the property sub-menu
		menuProperty = new JMenu( "Properties" );
		menuProperty.setMnemonic( 'P' );

		// Create property items
		menuPropertySystem = CreateMenuItem( menuProperty, ITEM_PLAIN,
								"System...", null, 'S', null );
		menuPropertyEditor = CreateMenuItem( menuProperty, ITEM_PLAIN,
								"Editor...", null, 'E', null );
		menuPropertyDisplay = CreateMenuItem( menuProperty, ITEM_PLAIN,
								"Display...", null, 'D', null );
		
		// Create the file menu
		menuFile = new JMenu( "File" );
		menuFile.setMnemonic( 'F' );
		menuBar.add( menuFile );

		// Create the file menu
		// Build a file menu items
		menuFileNew = CreateMenuItem( menuFile, ITEM_PLAIN,
								"New", null, 'N', null );
		menuFileOpen = CreateMenuItem( menuFile, ITEM_PLAIN, "Open...",
								new ImageIcon( "open.gif" ), 'O',
								"Open a new file" );
		menuFileSave = CreateMenuItem( menuFile, ITEM_PLAIN, "Save",
								new ImageIcon( "save.gif" ), 'S',
								" Save this file" );
		menuFileSaveAs = CreateMenuItem( menuFile, ITEM_PLAIN,
								"Save As...", null, 'A',
								"Save this data to a new file" );
		// Add the property menu
		menuFile.addSeparator();
		menuFile.add( menuProperty );	
		menuFile.addSeparator();
		menuFileExit = CreateMenuItem( menuFile, ITEM_PLAIN,
								"Exit", null, 'x',
								"Exit the program" );


		// Create the file menu
		menuEdit = new JMenu( "Edit" );
		menuEdit.setMnemonic( 'E' );
		menuBar.add( menuEdit );

		// Create edit menu options
		menuEditCut = CreateMenuItem( menuEdit, ITEM_PLAIN,
								"Cut", null, 't',
								"Cut data to the clipboard" );
		menuEditCopy = CreateMenuItem( menuEdit, ITEM_PLAIN,
								"Copy", null, 'C',
								"Copy data to the clipboard" );
		menuEditPaste = CreateMenuItem( menuEdit, ITEM_PLAIN,
								"Paste", null, 'P',
								"Paste data from the clipboard" );
	}

	public JMenuItem CreateMenuItem( JMenu menu, int iType, String sText,
								ImageIcon image, int acceleratorKey,
								String sToolTip )
	{
		// Create the item
		JMenuItem menuItem;

		switch( iType )
		{
			case ITEM_RADIO:
				menuItem = new JRadioButtonMenuItem();
				break;

			case ITEM_CHECK:
				menuItem = new JCheckBoxMenuItem();
				break;

			default:
				menuItem = new JMenuItem();
				break;
		}

		// Add the item test
		menuItem.setText( sText );

		// Add the optional icon
		if( image != null )
			menuItem.setIcon( image );

		// Add the accelerator key
		if( acceleratorKey > 0 )
			menuItem.setMnemonic( acceleratorKey );

		// Add the optional tool tip text
		if( sToolTip != null )
			menuItem.setToolTipText( sToolTip );

		// Add an action handler to this menu item
		menuItem.addActionListener( this );

		menu.add( menuItem );

		return menuItem;
	}
	public void actionPerformed( ActionEvent event )
	{
		System.out.println( event );
	}

	/**
	 * @param args
	 */
	public static void main(String[] args) {
		// TODO Auto-generated method stub
        MyJPTest myObj = new MyJPTest();
        myObj.setSize(200,200);
        myObj.setVisible(true);
	}

}
class MyJPanel extends JPanel{
	public MyJPanel(){
		super();
	}
	 public void paintComponent(Graphics g)
	    {
	        super.paintComponent(g);
	        g.setColor(Color.red);
	        g.drawString("Hello",50,100);
	    }

	    public Dimension getPreferredSize()
	    {
	        return new Dimension(400, 400);
	    }

	    public Dimension getMinimumSize()
	    {
	        return getPreferredSize();
	    }
	
}